The major thrust of this year's work has been to validate, refine, and extend the applications of respiratory inductive plethysmography. We are confident that the device is a practical semi-quantitative non-invasive monitor of breathing pattern at rest, exercise, sleep and bronchoconstriction. Thus, the whole range of non-invasive assessment of breathing patterns in the critically ill during sleep and in the ambulatory setting becomes practical and offers the same potential of early clinical diagnosis as has been the situation in cardiological monitoring over the past decade. The proposed work includes: a) non-invasive monitoring of breathing pattern during bronchoprovocation and deep breathing, b) assessment of breathing pattern in sheep during experimental pulmonary embolism, c) mechanism of pulmonary vasoconstrictive response during experimental pulmonary embolism, d) measurement of oxygen consumption on a breath basis using respiratory inductive plethysmography and mass spectrometry, e) establishing the relationship between changes in neck volume and intrapleural pressure, f) measurement of changes in carotid arterial blood volume by inductive plethysmography and correlation of systolic time intervals at rest and exercise, g) assessment of the relationship of the isovolume calibration procedure to validation of tidal volume measured by respiratory inductive plethysmography, and h) characterization of H1 and H2 receptor function in the pulmonary and systemic circulation of sheep.